Is the mid-term outcome of free right internal thoracic artery with a proximal anastomosis modification inferior to in situ right internal thoracic artery?

Abstract

We investigated the mid-term results of free right internal thoracic artery (RITA) grafts used in an aorto-coronary fashion with a modified proximal anastomosis. The subjects were 214 patients who underwent coronary artery bypass grafting with anastomosis to the left circumflex arteries using the RITA as a free graft (Group A: 158 patients) or an in situ graft (Group B: 56 patients). In Group A, the proximal end of the free RITA was anastomosed onto the ascending aorta interposing free graft tissue or to part of its own tissue as a cuff. The number of RITA anastomoses was 1.38±0.50 in Group A and 1.04±0.19 in Group B (P<0.001). The relationship between perioperative variables and mid-term outcomes was assessed using Cox proportional hazard models. Survival was not associated with the way the RITA graft was performed (Hazard Ratio 5.26, 95% CI 0.52-53.1, P=0.159), however, the number of cardiac events was decreased in Group A (Hazard Ratio 2.55, 95% CI 1.03-6.33, P=0.043). The graft patency was evaluated in 187 of 214 patients, and at 1, 3 and 5years was 97.0, 97.0 and 97.0% in Group A, and 97.9, 92.5 and 80.5% in Group B (P=0.378), respectively. By modifying the proximal anastomosis of the free RITA, cardiac events may be decreased, while survival and graft patency comparable with in situ RITA can be obtained, and a significantly larger number of targets can be revascularized.